[Scip] Fixed SCIP Soplex Problem (actually a glibc bug)

[Stefan Heinz]

Dear SCIP/SoPlex users,

several of you who worked with older versions of the GCC compiler have
encountered problems with SCIP 1.2 using SoPlex 1.4.2, resulting in many
"unresolved numerical troubles in LP" warning messages.

The reason seem to be that the current implementation of SoPlex's index
management triggers a bug hidden in the glibc library when used on 32bit
systems.

If you have problems we recommend either to update your compiler version
or to use the SoPlex patch 1.4.2b provided on the SoPlex homepage,
http://www.soplex.zib for download, providing an alternative
implementation of the file datakey.h.

Best regards,
the SCIP and SoPlex team